The equations express the effects of (1) social variables affecting public support in assisting and supporting police activities, (2) the number of police officers available as a percent of the community's population, (3) the number of criminal offenses committed, and (4) the number of crimes reported. The model is demonstrated using data collected as part of a British Home Office program planning budgeting study which provided unspecified demographic details and police activity information for 12 police forces for the 1971-72, 1973-74, and 1974-75 accounting years. Using these data, estimates were derived which indicated that an average hypothetical police force of 2,500 officers would be capable of recording about 11 percent of all community crime and of preventing about 41 percent of all crimes which could potentially occur in a hypothetically average community. A 10,000-officer force would record 52 percent of all crimes and prevent 78 percent of all potential crimes. The model, while not entirely accurate in predicting crime recording and prevention rates, compares satisfactorily with more expensive field surveys and controlled experiments. Better data and improved data analysis software would improve the model's predictability. A table, an appendix, and a bibliography of 12 references are included.